Alendronate for Bone Strength

What It Is Prescribed For

  • Prevention and treatment of osteoporosis (thinning of the bones) in postmenopausal women
  • Treatment of osteoporosis in men
  • Treatment of corticosteroid-induced osteoporosis
  • Treatment of Paget disease (thickening and softening of bones due to an abnormal increase in both bone breakdown and bone rebuilding)

How Alendronate Works

Rerun image Throughout life, bones are constantly being broken down and rebuilt. In the cases of osteoporosis and Paget disease, this natural cycle is altered. This change, along with other factors, leads to a loss of bone (osteoporosis), or loss of bone at some places in the body and thickening of bone in other places (Paget disease). Alendronate helps to improve overall bone mass by inhibiting its breakdown.

Precautions While Using This Medication

See Your Doctor Regularly

It is important that your doctor check your progress at regular visits, to allow for dosage adjustments and to help reduce side effects. The following information may affect your usage of alendronate, so be sure to tell your doctor if you are:

  • Pregnant or breastfeeding
  • Planning to be pregnant or breastfeeding
  • Following a special diet
  • Taking aspirin, products that contain aspirin, or other nonsteroidal anti-inflammatory drugs (NSAIDs)
  • Taking antacids (calcium) or ranitidine

Be Cautious With Certain Medical Conditions

Alendronate may make some medical conditions worse. Tell your doctor if you have any medical problems, especially:

  • Stomach, intestinal, or esophageal problems
  • Kidney problems
  • Low level of blood calcium or vitamin D deficiency

Proper Use

Take on an Empty Stomach

Take alendronate in the morning on an empty stomach. Take with a full glass of plain water and wait at least 30 minutes before consuming any food, beverage, or other medicines. Food and beverages other than plain water will decrease the amount of alendronate absorbed by the body. Medications, such as antacids, or calcium or vitamin supplements, will also decrease absorption. Waiting at least 30 minutes allows for more of the drug to be absorbed.

Don't Lie Down

Do not lie down for 30 minutes after taking this drug. Staying upright will help the alendronate reach your stomach faster, and will help prevent irritation in your throat.

Follow Dietary Recommendations

Rerun Image You may be advised to increase the amount of calcium and vitamin D in your diet. Both of these nutrients are important for bone health. You can get these nutrients through foods, but your doctor may also recommend a supplement.

Sources of calcium include:

  • Milk, yogurt, cheese, and other dairy products
  • Calcium-fortified juices and breakfast cereals
  • Sardines and salmon with bones
  • Leafy green vegetables, such as spinach, kale, and turnip greens

Sources of vitamin D include:

  • Fortified milk
  • Fish oil
  • Sunshine; your body can make vitamin D with the sunlight absorbed through your skin

Missed Dose

Take a missed dose as soon as possible. If you miss a daily dose, resume the next day. If you miss a weekly dose, resume the next day and again the following week on the scheduled day. Do not double up on doses.

Possible Side Effects

Check with your doctor as soon as possible if any of the following side effects occur:

  • Abdominal pain
  • Vomiting
  • Difficulty swallowing
  • Heartburn
  • Irritation or pain of the esophagus
  • Black or tarry stools
  • Skin rash or swelling (rare)

Check with your doctor if any of the following side effects occur frequently and/or become bothersome:

  • Constipation
  • Diarrhea
  • Full or bloated feeling
  • Gas
  • Headache
  • Nausea
  • Bone, muscle, or joint pain


The National Institutes of Health Osteoporosis and Related Bone Diseases
US Food and Drug Administration


The College of Family Physicians of Canada
College of Pharmacists of British Columbia


Alendronate. EBSCO DynaMed Plus website. Available at: Updated July 7, 2017. Accessed July 31, 2017.
Fosamax (alendronate sodium tablet). US National Library of Medicine Daily Med website. Available at:
...(Click grey area to select URL)
Updated March 21, 2016. Accessed July 31, 2017.
Osteoporosis. EBSCO DynaMed Plus website. Available at: Updated July 26, 2017. Accessed July 31, 2017.
Last reviewed July 2017 by Michael Woods, MD, FAAP
Last Updated: 8/12/2015

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